Not sure, but it must be a little bit easier for clubs with stadiums that aren't mad miles away from the main town/city. However, I still maintain that it's a ballache getting tens of thousands of people out of a venue at the same time, regardless of where it is situated.
It's funny (and I don't mean to rile anyone with my experience) because the return journey on the Mill Road P&R was one of the quickest and most straightforward transfers there's been this season.